The invention relates to an apparatus for turning flat shipments, which are delivered in succession standing on their short sides by a conveyor system, into a recumbent position without interrupting the conveying.
In sorting machines, the shipments are separated out from a stack in the inlet portion. To keep the size of the stack from affecting the payout quality, the stack reaches a horizontally oriented feeder bed, where the shipments stand on their short side. The shipments are then paid out in the upright position. In order the distribute the shipments subsequently to an optimal number of sorting compartment while requiring little machine space, it is advantages to stack the shipments in a recumbent position. This makes it possible to place a plurality of compartments one above the other.
It therefore follows that the shipments, during their travel through the sorting machine, much be changed from the position in which they stand on their short sides into a recumbent position. This task is accomplished in an apparatus for turning the shipments. The shipments undergo a rotation about their longitudinal axis by an amount between 90.degree. and 70.degree., depending on whether the shipments in their recumbent position are oriented horizontally or in sloping fashion.
Embodiments in which the shipments are clamped between driven belts and conveyed through the sorting machine are known. For turning, the belts are correspondingly twisted. This procedure has stood the test of time for post cards and standard-sized letters. For handling a wider range of shipments, however, from thin, lightweight post cards to heavy, large envelopes, however, this principle cannot assure reliable, space-saving operation. This is because belt clamping does not assure secure, nonslip conveyance of the heavy shipments, and if a thick shipment is followed by a thin one, the latter will not be grasped tightly enough by the belts that are still spread apart. This effect could be avoided only with very long spacings between shipments.
A turning apparatus would thus have to be very long, with unusually long gaps between shipments, making the machine less productive. One way of avoiding or lessening these disadvantages has become known in which the twisted belts are additionally pressed together by spring-supported rollers. This is complicated and does not assure reliable function, since the rollers affect belt travel, and the belt travel has to be compensated for via a control roller.